xref: /openbmc/linux/fs/f2fs/super.c (revision 93d90ad7)
1 /*
2  * fs/f2fs/super.c
3  *
4  * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5  *             http://www.samsung.com/
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/fs.h>
14 #include <linux/statfs.h>
15 #include <linux/buffer_head.h>
16 #include <linux/backing-dev.h>
17 #include <linux/kthread.h>
18 #include <linux/parser.h>
19 #include <linux/mount.h>
20 #include <linux/seq_file.h>
21 #include <linux/proc_fs.h>
22 #include <linux/random.h>
23 #include <linux/exportfs.h>
24 #include <linux/blkdev.h>
25 #include <linux/f2fs_fs.h>
26 #include <linux/sysfs.h>
27 
28 #include "f2fs.h"
29 #include "node.h"
30 #include "segment.h"
31 #include "xattr.h"
32 #include "gc.h"
33 
34 #define CREATE_TRACE_POINTS
35 #include <trace/events/f2fs.h>
36 
37 static struct proc_dir_entry *f2fs_proc_root;
38 static struct kmem_cache *f2fs_inode_cachep;
39 static struct kset *f2fs_kset;
40 
41 enum {
42 	Opt_gc_background,
43 	Opt_disable_roll_forward,
44 	Opt_discard,
45 	Opt_noheap,
46 	Opt_user_xattr,
47 	Opt_nouser_xattr,
48 	Opt_acl,
49 	Opt_noacl,
50 	Opt_active_logs,
51 	Opt_disable_ext_identify,
52 	Opt_inline_xattr,
53 	Opt_inline_data,
54 	Opt_inline_dentry,
55 	Opt_flush_merge,
56 	Opt_nobarrier,
57 	Opt_fastboot,
58 	Opt_err,
59 };
60 
61 static match_table_t f2fs_tokens = {
62 	{Opt_gc_background, "background_gc=%s"},
63 	{Opt_disable_roll_forward, "disable_roll_forward"},
64 	{Opt_discard, "discard"},
65 	{Opt_noheap, "no_heap"},
66 	{Opt_user_xattr, "user_xattr"},
67 	{Opt_nouser_xattr, "nouser_xattr"},
68 	{Opt_acl, "acl"},
69 	{Opt_noacl, "noacl"},
70 	{Opt_active_logs, "active_logs=%u"},
71 	{Opt_disable_ext_identify, "disable_ext_identify"},
72 	{Opt_inline_xattr, "inline_xattr"},
73 	{Opt_inline_data, "inline_data"},
74 	{Opt_inline_dentry, "inline_dentry"},
75 	{Opt_flush_merge, "flush_merge"},
76 	{Opt_nobarrier, "nobarrier"},
77 	{Opt_fastboot, "fastboot"},
78 	{Opt_err, NULL},
79 };
80 
81 /* Sysfs support for f2fs */
82 enum {
83 	GC_THREAD,	/* struct f2fs_gc_thread */
84 	SM_INFO,	/* struct f2fs_sm_info */
85 	NM_INFO,	/* struct f2fs_nm_info */
86 	F2FS_SBI,	/* struct f2fs_sb_info */
87 };
88 
89 struct f2fs_attr {
90 	struct attribute attr;
91 	ssize_t (*show)(struct f2fs_attr *, struct f2fs_sb_info *, char *);
92 	ssize_t (*store)(struct f2fs_attr *, struct f2fs_sb_info *,
93 			 const char *, size_t);
94 	int struct_type;
95 	int offset;
96 };
97 
98 static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
99 {
100 	if (struct_type == GC_THREAD)
101 		return (unsigned char *)sbi->gc_thread;
102 	else if (struct_type == SM_INFO)
103 		return (unsigned char *)SM_I(sbi);
104 	else if (struct_type == NM_INFO)
105 		return (unsigned char *)NM_I(sbi);
106 	else if (struct_type == F2FS_SBI)
107 		return (unsigned char *)sbi;
108 	return NULL;
109 }
110 
111 static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
112 			struct f2fs_sb_info *sbi, char *buf)
113 {
114 	unsigned char *ptr = NULL;
115 	unsigned int *ui;
116 
117 	ptr = __struct_ptr(sbi, a->struct_type);
118 	if (!ptr)
119 		return -EINVAL;
120 
121 	ui = (unsigned int *)(ptr + a->offset);
122 
123 	return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
124 }
125 
126 static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
127 			struct f2fs_sb_info *sbi,
128 			const char *buf, size_t count)
129 {
130 	unsigned char *ptr;
131 	unsigned long t;
132 	unsigned int *ui;
133 	ssize_t ret;
134 
135 	ptr = __struct_ptr(sbi, a->struct_type);
136 	if (!ptr)
137 		return -EINVAL;
138 
139 	ui = (unsigned int *)(ptr + a->offset);
140 
141 	ret = kstrtoul(skip_spaces(buf), 0, &t);
142 	if (ret < 0)
143 		return ret;
144 	*ui = t;
145 	return count;
146 }
147 
148 static ssize_t f2fs_attr_show(struct kobject *kobj,
149 				struct attribute *attr, char *buf)
150 {
151 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
152 								s_kobj);
153 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
154 
155 	return a->show ? a->show(a, sbi, buf) : 0;
156 }
157 
158 static ssize_t f2fs_attr_store(struct kobject *kobj, struct attribute *attr,
159 						const char *buf, size_t len)
160 {
161 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
162 									s_kobj);
163 	struct f2fs_attr *a = container_of(attr, struct f2fs_attr, attr);
164 
165 	return a->store ? a->store(a, sbi, buf, len) : 0;
166 }
167 
168 static void f2fs_sb_release(struct kobject *kobj)
169 {
170 	struct f2fs_sb_info *sbi = container_of(kobj, struct f2fs_sb_info,
171 								s_kobj);
172 	complete(&sbi->s_kobj_unregister);
173 }
174 
175 #define F2FS_ATTR_OFFSET(_struct_type, _name, _mode, _show, _store, _offset) \
176 static struct f2fs_attr f2fs_attr_##_name = {			\
177 	.attr = {.name = __stringify(_name), .mode = _mode },	\
178 	.show	= _show,					\
179 	.store	= _store,					\
180 	.struct_type = _struct_type,				\
181 	.offset = _offset					\
182 }
183 
184 #define F2FS_RW_ATTR(struct_type, struct_name, name, elname)	\
185 	F2FS_ATTR_OFFSET(struct_type, name, 0644,		\
186 		f2fs_sbi_show, f2fs_sbi_store,			\
187 		offsetof(struct struct_name, elname))
188 
189 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_min_sleep_time, min_sleep_time);
190 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_max_sleep_time, max_sleep_time);
191 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_no_gc_sleep_time, no_gc_sleep_time);
192 F2FS_RW_ATTR(GC_THREAD, f2fs_gc_kthread, gc_idle, gc_idle);
193 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, reclaim_segments, rec_prefree_segments);
194 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, max_small_discards, max_discards);
195 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, ipu_policy, ipu_policy);
196 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_ipu_util, min_ipu_util);
197 F2FS_RW_ATTR(SM_INFO, f2fs_sm_info, min_fsync_blocks, min_fsync_blocks);
198 F2FS_RW_ATTR(NM_INFO, f2fs_nm_info, ram_thresh, ram_thresh);
199 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_victim_search, max_victim_search);
200 F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, dir_level, dir_level);
201 
202 #define ATTR_LIST(name) (&f2fs_attr_##name.attr)
203 static struct attribute *f2fs_attrs[] = {
204 	ATTR_LIST(gc_min_sleep_time),
205 	ATTR_LIST(gc_max_sleep_time),
206 	ATTR_LIST(gc_no_gc_sleep_time),
207 	ATTR_LIST(gc_idle),
208 	ATTR_LIST(reclaim_segments),
209 	ATTR_LIST(max_small_discards),
210 	ATTR_LIST(ipu_policy),
211 	ATTR_LIST(min_ipu_util),
212 	ATTR_LIST(min_fsync_blocks),
213 	ATTR_LIST(max_victim_search),
214 	ATTR_LIST(dir_level),
215 	ATTR_LIST(ram_thresh),
216 	NULL,
217 };
218 
219 static const struct sysfs_ops f2fs_attr_ops = {
220 	.show	= f2fs_attr_show,
221 	.store	= f2fs_attr_store,
222 };
223 
224 static struct kobj_type f2fs_ktype = {
225 	.default_attrs	= f2fs_attrs,
226 	.sysfs_ops	= &f2fs_attr_ops,
227 	.release	= f2fs_sb_release,
228 };
229 
230 void f2fs_msg(struct super_block *sb, const char *level, const char *fmt, ...)
231 {
232 	struct va_format vaf;
233 	va_list args;
234 
235 	va_start(args, fmt);
236 	vaf.fmt = fmt;
237 	vaf.va = &args;
238 	printk("%sF2FS-fs (%s): %pV\n", level, sb->s_id, &vaf);
239 	va_end(args);
240 }
241 
242 static void init_once(void *foo)
243 {
244 	struct f2fs_inode_info *fi = (struct f2fs_inode_info *) foo;
245 
246 	inode_init_once(&fi->vfs_inode);
247 }
248 
249 static int parse_options(struct super_block *sb, char *options)
250 {
251 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
252 	substring_t args[MAX_OPT_ARGS];
253 	char *p, *name;
254 	int arg = 0;
255 
256 	if (!options)
257 		return 0;
258 
259 	while ((p = strsep(&options, ",")) != NULL) {
260 		int token;
261 		if (!*p)
262 			continue;
263 		/*
264 		 * Initialize args struct so we know whether arg was
265 		 * found; some options take optional arguments.
266 		 */
267 		args[0].to = args[0].from = NULL;
268 		token = match_token(p, f2fs_tokens, args);
269 
270 		switch (token) {
271 		case Opt_gc_background:
272 			name = match_strdup(&args[0]);
273 
274 			if (!name)
275 				return -ENOMEM;
276 			if (strlen(name) == 2 && !strncmp(name, "on", 2))
277 				set_opt(sbi, BG_GC);
278 			else if (strlen(name) == 3 && !strncmp(name, "off", 3))
279 				clear_opt(sbi, BG_GC);
280 			else {
281 				kfree(name);
282 				return -EINVAL;
283 			}
284 			kfree(name);
285 			break;
286 		case Opt_disable_roll_forward:
287 			set_opt(sbi, DISABLE_ROLL_FORWARD);
288 			break;
289 		case Opt_discard:
290 			set_opt(sbi, DISCARD);
291 			break;
292 		case Opt_noheap:
293 			set_opt(sbi, NOHEAP);
294 			break;
295 #ifdef CONFIG_F2FS_FS_XATTR
296 		case Opt_user_xattr:
297 			set_opt(sbi, XATTR_USER);
298 			break;
299 		case Opt_nouser_xattr:
300 			clear_opt(sbi, XATTR_USER);
301 			break;
302 		case Opt_inline_xattr:
303 			set_opt(sbi, INLINE_XATTR);
304 			break;
305 #else
306 		case Opt_user_xattr:
307 			f2fs_msg(sb, KERN_INFO,
308 				"user_xattr options not supported");
309 			break;
310 		case Opt_nouser_xattr:
311 			f2fs_msg(sb, KERN_INFO,
312 				"nouser_xattr options not supported");
313 			break;
314 		case Opt_inline_xattr:
315 			f2fs_msg(sb, KERN_INFO,
316 				"inline_xattr options not supported");
317 			break;
318 #endif
319 #ifdef CONFIG_F2FS_FS_POSIX_ACL
320 		case Opt_acl:
321 			set_opt(sbi, POSIX_ACL);
322 			break;
323 		case Opt_noacl:
324 			clear_opt(sbi, POSIX_ACL);
325 			break;
326 #else
327 		case Opt_acl:
328 			f2fs_msg(sb, KERN_INFO, "acl options not supported");
329 			break;
330 		case Opt_noacl:
331 			f2fs_msg(sb, KERN_INFO, "noacl options not supported");
332 			break;
333 #endif
334 		case Opt_active_logs:
335 			if (args->from && match_int(args, &arg))
336 				return -EINVAL;
337 			if (arg != 2 && arg != 4 && arg != NR_CURSEG_TYPE)
338 				return -EINVAL;
339 			sbi->active_logs = arg;
340 			break;
341 		case Opt_disable_ext_identify:
342 			set_opt(sbi, DISABLE_EXT_IDENTIFY);
343 			break;
344 		case Opt_inline_data:
345 			set_opt(sbi, INLINE_DATA);
346 			break;
347 		case Opt_inline_dentry:
348 			set_opt(sbi, INLINE_DENTRY);
349 			break;
350 		case Opt_flush_merge:
351 			set_opt(sbi, FLUSH_MERGE);
352 			break;
353 		case Opt_nobarrier:
354 			set_opt(sbi, NOBARRIER);
355 			break;
356 		case Opt_fastboot:
357 			set_opt(sbi, FASTBOOT);
358 			break;
359 		default:
360 			f2fs_msg(sb, KERN_ERR,
361 				"Unrecognized mount option \"%s\" or missing value",
362 				p);
363 			return -EINVAL;
364 		}
365 	}
366 	return 0;
367 }
368 
369 static struct inode *f2fs_alloc_inode(struct super_block *sb)
370 {
371 	struct f2fs_inode_info *fi;
372 
373 	fi = kmem_cache_alloc(f2fs_inode_cachep, GFP_F2FS_ZERO);
374 	if (!fi)
375 		return NULL;
376 
377 	init_once((void *) fi);
378 
379 	/* Initialize f2fs-specific inode info */
380 	fi->vfs_inode.i_version = 1;
381 	atomic_set(&fi->dirty_pages, 0);
382 	fi->i_current_depth = 1;
383 	fi->i_advise = 0;
384 	rwlock_init(&fi->ext.ext_lock);
385 	init_rwsem(&fi->i_sem);
386 	INIT_RADIX_TREE(&fi->inmem_root, GFP_NOFS);
387 	INIT_LIST_HEAD(&fi->inmem_pages);
388 	mutex_init(&fi->inmem_lock);
389 
390 	set_inode_flag(fi, FI_NEW_INODE);
391 
392 	if (test_opt(F2FS_SB(sb), INLINE_XATTR))
393 		set_inode_flag(fi, FI_INLINE_XATTR);
394 
395 	/* Will be used by directory only */
396 	fi->i_dir_level = F2FS_SB(sb)->dir_level;
397 
398 	return &fi->vfs_inode;
399 }
400 
401 static int f2fs_drop_inode(struct inode *inode)
402 {
403 	/*
404 	 * This is to avoid a deadlock condition like below.
405 	 * writeback_single_inode(inode)
406 	 *  - f2fs_write_data_page
407 	 *    - f2fs_gc -> iput -> evict
408 	 *       - inode_wait_for_writeback(inode)
409 	 */
410 	if (!inode_unhashed(inode) && inode->i_state & I_SYNC)
411 		return 0;
412 	return generic_drop_inode(inode);
413 }
414 
415 /*
416  * f2fs_dirty_inode() is called from __mark_inode_dirty()
417  *
418  * We should call set_dirty_inode to write the dirty inode through write_inode.
419  */
420 static void f2fs_dirty_inode(struct inode *inode, int flags)
421 {
422 	set_inode_flag(F2FS_I(inode), FI_DIRTY_INODE);
423 }
424 
425 static void f2fs_i_callback(struct rcu_head *head)
426 {
427 	struct inode *inode = container_of(head, struct inode, i_rcu);
428 	kmem_cache_free(f2fs_inode_cachep, F2FS_I(inode));
429 }
430 
431 static void f2fs_destroy_inode(struct inode *inode)
432 {
433 	call_rcu(&inode->i_rcu, f2fs_i_callback);
434 }
435 
436 static void f2fs_put_super(struct super_block *sb)
437 {
438 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
439 
440 	if (sbi->s_proc) {
441 		remove_proc_entry("segment_info", sbi->s_proc);
442 		remove_proc_entry(sb->s_id, f2fs_proc_root);
443 	}
444 	kobject_del(&sbi->s_kobj);
445 
446 	f2fs_destroy_stats(sbi);
447 	stop_gc_thread(sbi);
448 
449 	/* We don't need to do checkpoint when it's clean */
450 	if (sbi->s_dirty) {
451 		struct cp_control cpc = {
452 			.reason = CP_UMOUNT,
453 		};
454 		write_checkpoint(sbi, &cpc);
455 	}
456 
457 	/*
458 	 * normally superblock is clean, so we need to release this.
459 	 * In addition, EIO will skip do checkpoint, we need this as well.
460 	 */
461 	release_dirty_inode(sbi);
462 	release_discard_addrs(sbi);
463 
464 	iput(sbi->node_inode);
465 	iput(sbi->meta_inode);
466 
467 	/* destroy f2fs internal modules */
468 	destroy_node_manager(sbi);
469 	destroy_segment_manager(sbi);
470 
471 	kfree(sbi->ckpt);
472 	kobject_put(&sbi->s_kobj);
473 	wait_for_completion(&sbi->s_kobj_unregister);
474 
475 	sb->s_fs_info = NULL;
476 	brelse(sbi->raw_super_buf);
477 	kfree(sbi);
478 }
479 
480 int f2fs_sync_fs(struct super_block *sb, int sync)
481 {
482 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
483 
484 	trace_f2fs_sync_fs(sb, sync);
485 
486 	if (sync) {
487 		struct cp_control cpc;
488 
489 		cpc.reason = test_opt(sbi, FASTBOOT) ? CP_UMOUNT : CP_SYNC;
490 		mutex_lock(&sbi->gc_mutex);
491 		write_checkpoint(sbi, &cpc);
492 		mutex_unlock(&sbi->gc_mutex);
493 	} else {
494 		f2fs_balance_fs(sbi);
495 	}
496 
497 	return 0;
498 }
499 
500 static int f2fs_freeze(struct super_block *sb)
501 {
502 	int err;
503 
504 	if (f2fs_readonly(sb))
505 		return 0;
506 
507 	err = f2fs_sync_fs(sb, 1);
508 	return err;
509 }
510 
511 static int f2fs_unfreeze(struct super_block *sb)
512 {
513 	return 0;
514 }
515 
516 static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
517 {
518 	struct super_block *sb = dentry->d_sb;
519 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
520 	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
521 	block_t total_count, user_block_count, start_count, ovp_count;
522 
523 	total_count = le64_to_cpu(sbi->raw_super->block_count);
524 	user_block_count = sbi->user_block_count;
525 	start_count = le32_to_cpu(sbi->raw_super->segment0_blkaddr);
526 	ovp_count = SM_I(sbi)->ovp_segments << sbi->log_blocks_per_seg;
527 	buf->f_type = F2FS_SUPER_MAGIC;
528 	buf->f_bsize = sbi->blocksize;
529 
530 	buf->f_blocks = total_count - start_count;
531 	buf->f_bfree = buf->f_blocks - valid_user_blocks(sbi) - ovp_count;
532 	buf->f_bavail = user_block_count - valid_user_blocks(sbi);
533 
534 	buf->f_files = sbi->total_node_count - F2FS_RESERVED_NODE_NUM;
535 	buf->f_ffree = buf->f_files - valid_inode_count(sbi);
536 
537 	buf->f_namelen = F2FS_NAME_LEN;
538 	buf->f_fsid.val[0] = (u32)id;
539 	buf->f_fsid.val[1] = (u32)(id >> 32);
540 
541 	return 0;
542 }
543 
544 static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
545 {
546 	struct f2fs_sb_info *sbi = F2FS_SB(root->d_sb);
547 
548 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, BG_GC))
549 		seq_printf(seq, ",background_gc=%s", "on");
550 	else
551 		seq_printf(seq, ",background_gc=%s", "off");
552 	if (test_opt(sbi, DISABLE_ROLL_FORWARD))
553 		seq_puts(seq, ",disable_roll_forward");
554 	if (test_opt(sbi, DISCARD))
555 		seq_puts(seq, ",discard");
556 	if (test_opt(sbi, NOHEAP))
557 		seq_puts(seq, ",no_heap_alloc");
558 #ifdef CONFIG_F2FS_FS_XATTR
559 	if (test_opt(sbi, XATTR_USER))
560 		seq_puts(seq, ",user_xattr");
561 	else
562 		seq_puts(seq, ",nouser_xattr");
563 	if (test_opt(sbi, INLINE_XATTR))
564 		seq_puts(seq, ",inline_xattr");
565 #endif
566 #ifdef CONFIG_F2FS_FS_POSIX_ACL
567 	if (test_opt(sbi, POSIX_ACL))
568 		seq_puts(seq, ",acl");
569 	else
570 		seq_puts(seq, ",noacl");
571 #endif
572 	if (test_opt(sbi, DISABLE_EXT_IDENTIFY))
573 		seq_puts(seq, ",disable_ext_identify");
574 	if (test_opt(sbi, INLINE_DATA))
575 		seq_puts(seq, ",inline_data");
576 	if (test_opt(sbi, INLINE_DENTRY))
577 		seq_puts(seq, ",inline_dentry");
578 	if (!f2fs_readonly(sbi->sb) && test_opt(sbi, FLUSH_MERGE))
579 		seq_puts(seq, ",flush_merge");
580 	if (test_opt(sbi, NOBARRIER))
581 		seq_puts(seq, ",nobarrier");
582 	if (test_opt(sbi, FASTBOOT))
583 		seq_puts(seq, ",fastboot");
584 	seq_printf(seq, ",active_logs=%u", sbi->active_logs);
585 
586 	return 0;
587 }
588 
589 static int segment_info_seq_show(struct seq_file *seq, void *offset)
590 {
591 	struct super_block *sb = seq->private;
592 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
593 	unsigned int total_segs =
594 			le32_to_cpu(sbi->raw_super->segment_count_main);
595 	int i;
596 
597 	seq_puts(seq, "format: segment_type|valid_blocks\n"
598 		"segment_type(0:HD, 1:WD, 2:CD, 3:HN, 4:WN, 5:CN)\n");
599 
600 	for (i = 0; i < total_segs; i++) {
601 		struct seg_entry *se = get_seg_entry(sbi, i);
602 
603 		if ((i % 10) == 0)
604 			seq_printf(seq, "%-5d", i);
605 		seq_printf(seq, "%d|%-3u", se->type,
606 					get_valid_blocks(sbi, i, 1));
607 		if ((i % 10) == 9 || i == (total_segs - 1))
608 			seq_putc(seq, '\n');
609 		else
610 			seq_putc(seq, ' ');
611 	}
612 
613 	return 0;
614 }
615 
616 static int segment_info_open_fs(struct inode *inode, struct file *file)
617 {
618 	return single_open(file, segment_info_seq_show, PDE_DATA(inode));
619 }
620 
621 static const struct file_operations f2fs_seq_segment_info_fops = {
622 	.owner = THIS_MODULE,
623 	.open = segment_info_open_fs,
624 	.read = seq_read,
625 	.llseek = seq_lseek,
626 	.release = single_release,
627 };
628 
629 static int f2fs_remount(struct super_block *sb, int *flags, char *data)
630 {
631 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
632 	struct f2fs_mount_info org_mount_opt;
633 	int err, active_logs;
634 	bool need_restart_gc = false;
635 	bool need_stop_gc = false;
636 
637 	sync_filesystem(sb);
638 
639 	/*
640 	 * Save the old mount options in case we
641 	 * need to restore them.
642 	 */
643 	org_mount_opt = sbi->mount_opt;
644 	active_logs = sbi->active_logs;
645 
646 	sbi->mount_opt.opt = 0;
647 	sbi->active_logs = NR_CURSEG_TYPE;
648 
649 	/* parse mount options */
650 	err = parse_options(sb, data);
651 	if (err)
652 		goto restore_opts;
653 
654 	/*
655 	 * Previous and new state of filesystem is RO,
656 	 * so skip checking GC and FLUSH_MERGE conditions.
657 	 */
658 	if (f2fs_readonly(sb) && (*flags & MS_RDONLY))
659 		goto skip;
660 
661 	/*
662 	 * We stop the GC thread if FS is mounted as RO
663 	 * or if background_gc = off is passed in mount
664 	 * option. Also sync the filesystem.
665 	 */
666 	if ((*flags & MS_RDONLY) || !test_opt(sbi, BG_GC)) {
667 		if (sbi->gc_thread) {
668 			stop_gc_thread(sbi);
669 			f2fs_sync_fs(sb, 1);
670 			need_restart_gc = true;
671 		}
672 	} else if (!sbi->gc_thread) {
673 		err = start_gc_thread(sbi);
674 		if (err)
675 			goto restore_opts;
676 		need_stop_gc = true;
677 	}
678 
679 	/*
680 	 * We stop issue flush thread if FS is mounted as RO
681 	 * or if flush_merge is not passed in mount option.
682 	 */
683 	if ((*flags & MS_RDONLY) || !test_opt(sbi, FLUSH_MERGE)) {
684 		destroy_flush_cmd_control(sbi);
685 	} else if (!SM_I(sbi)->cmd_control_info) {
686 		err = create_flush_cmd_control(sbi);
687 		if (err)
688 			goto restore_gc;
689 	}
690 skip:
691 	/* Update the POSIXACL Flag */
692 	 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
693 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
694 	return 0;
695 restore_gc:
696 	if (need_restart_gc) {
697 		if (start_gc_thread(sbi))
698 			f2fs_msg(sbi->sb, KERN_WARNING,
699 				"background gc thread has stopped");
700 	} else if (need_stop_gc) {
701 		stop_gc_thread(sbi);
702 	}
703 restore_opts:
704 	sbi->mount_opt = org_mount_opt;
705 	sbi->active_logs = active_logs;
706 	return err;
707 }
708 
709 static struct super_operations f2fs_sops = {
710 	.alloc_inode	= f2fs_alloc_inode,
711 	.drop_inode	= f2fs_drop_inode,
712 	.destroy_inode	= f2fs_destroy_inode,
713 	.write_inode	= f2fs_write_inode,
714 	.dirty_inode	= f2fs_dirty_inode,
715 	.show_options	= f2fs_show_options,
716 	.evict_inode	= f2fs_evict_inode,
717 	.put_super	= f2fs_put_super,
718 	.sync_fs	= f2fs_sync_fs,
719 	.freeze_fs	= f2fs_freeze,
720 	.unfreeze_fs	= f2fs_unfreeze,
721 	.statfs		= f2fs_statfs,
722 	.remount_fs	= f2fs_remount,
723 };
724 
725 static struct inode *f2fs_nfs_get_inode(struct super_block *sb,
726 		u64 ino, u32 generation)
727 {
728 	struct f2fs_sb_info *sbi = F2FS_SB(sb);
729 	struct inode *inode;
730 
731 	if (check_nid_range(sbi, ino))
732 		return ERR_PTR(-ESTALE);
733 
734 	/*
735 	 * f2fs_iget isn't quite right if the inode is currently unallocated!
736 	 * However f2fs_iget currently does appropriate checks to handle stale
737 	 * inodes so everything is OK.
738 	 */
739 	inode = f2fs_iget(sb, ino);
740 	if (IS_ERR(inode))
741 		return ERR_CAST(inode);
742 	if (unlikely(generation && inode->i_generation != generation)) {
743 		/* we didn't find the right inode.. */
744 		iput(inode);
745 		return ERR_PTR(-ESTALE);
746 	}
747 	return inode;
748 }
749 
750 static struct dentry *f2fs_fh_to_dentry(struct super_block *sb, struct fid *fid,
751 		int fh_len, int fh_type)
752 {
753 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
754 				    f2fs_nfs_get_inode);
755 }
756 
757 static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid,
758 		int fh_len, int fh_type)
759 {
760 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
761 				    f2fs_nfs_get_inode);
762 }
763 
764 static const struct export_operations f2fs_export_ops = {
765 	.fh_to_dentry = f2fs_fh_to_dentry,
766 	.fh_to_parent = f2fs_fh_to_parent,
767 	.get_parent = f2fs_get_parent,
768 };
769 
770 static loff_t max_file_size(unsigned bits)
771 {
772 	loff_t result = (DEF_ADDRS_PER_INODE - F2FS_INLINE_XATTR_ADDRS);
773 	loff_t leaf_count = ADDRS_PER_BLOCK;
774 
775 	/* two direct node blocks */
776 	result += (leaf_count * 2);
777 
778 	/* two indirect node blocks */
779 	leaf_count *= NIDS_PER_BLOCK;
780 	result += (leaf_count * 2);
781 
782 	/* one double indirect node block */
783 	leaf_count *= NIDS_PER_BLOCK;
784 	result += leaf_count;
785 
786 	result <<= bits;
787 	return result;
788 }
789 
790 static int sanity_check_raw_super(struct super_block *sb,
791 			struct f2fs_super_block *raw_super)
792 {
793 	unsigned int blocksize;
794 
795 	if (F2FS_SUPER_MAGIC != le32_to_cpu(raw_super->magic)) {
796 		f2fs_msg(sb, KERN_INFO,
797 			"Magic Mismatch, valid(0x%x) - read(0x%x)",
798 			F2FS_SUPER_MAGIC, le32_to_cpu(raw_super->magic));
799 		return 1;
800 	}
801 
802 	/* Currently, support only 4KB page cache size */
803 	if (F2FS_BLKSIZE != PAGE_CACHE_SIZE) {
804 		f2fs_msg(sb, KERN_INFO,
805 			"Invalid page_cache_size (%lu), supports only 4KB\n",
806 			PAGE_CACHE_SIZE);
807 		return 1;
808 	}
809 
810 	/* Currently, support only 4KB block size */
811 	blocksize = 1 << le32_to_cpu(raw_super->log_blocksize);
812 	if (blocksize != F2FS_BLKSIZE) {
813 		f2fs_msg(sb, KERN_INFO,
814 			"Invalid blocksize (%u), supports only 4KB\n",
815 			blocksize);
816 		return 1;
817 	}
818 
819 	/* Currently, support 512/1024/2048/4096 bytes sector size */
820 	if (le32_to_cpu(raw_super->log_sectorsize) >
821 				F2FS_MAX_LOG_SECTOR_SIZE ||
822 		le32_to_cpu(raw_super->log_sectorsize) <
823 				F2FS_MIN_LOG_SECTOR_SIZE) {
824 		f2fs_msg(sb, KERN_INFO, "Invalid log sectorsize (%u)",
825 			le32_to_cpu(raw_super->log_sectorsize));
826 		return 1;
827 	}
828 	if (le32_to_cpu(raw_super->log_sectors_per_block) +
829 		le32_to_cpu(raw_super->log_sectorsize) !=
830 			F2FS_MAX_LOG_SECTOR_SIZE) {
831 		f2fs_msg(sb, KERN_INFO,
832 			"Invalid log sectors per block(%u) log sectorsize(%u)",
833 			le32_to_cpu(raw_super->log_sectors_per_block),
834 			le32_to_cpu(raw_super->log_sectorsize));
835 		return 1;
836 	}
837 	return 0;
838 }
839 
840 static int sanity_check_ckpt(struct f2fs_sb_info *sbi)
841 {
842 	unsigned int total, fsmeta;
843 	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
844 	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
845 
846 	total = le32_to_cpu(raw_super->segment_count);
847 	fsmeta = le32_to_cpu(raw_super->segment_count_ckpt);
848 	fsmeta += le32_to_cpu(raw_super->segment_count_sit);
849 	fsmeta += le32_to_cpu(raw_super->segment_count_nat);
850 	fsmeta += le32_to_cpu(ckpt->rsvd_segment_count);
851 	fsmeta += le32_to_cpu(raw_super->segment_count_ssa);
852 
853 	if (unlikely(fsmeta >= total))
854 		return 1;
855 
856 	if (unlikely(f2fs_cp_error(sbi))) {
857 		f2fs_msg(sbi->sb, KERN_ERR, "A bug case: need to run fsck");
858 		return 1;
859 	}
860 	return 0;
861 }
862 
863 static void init_sb_info(struct f2fs_sb_info *sbi)
864 {
865 	struct f2fs_super_block *raw_super = sbi->raw_super;
866 	int i;
867 
868 	sbi->log_sectors_per_block =
869 		le32_to_cpu(raw_super->log_sectors_per_block);
870 	sbi->log_blocksize = le32_to_cpu(raw_super->log_blocksize);
871 	sbi->blocksize = 1 << sbi->log_blocksize;
872 	sbi->log_blocks_per_seg = le32_to_cpu(raw_super->log_blocks_per_seg);
873 	sbi->blocks_per_seg = 1 << sbi->log_blocks_per_seg;
874 	sbi->segs_per_sec = le32_to_cpu(raw_super->segs_per_sec);
875 	sbi->secs_per_zone = le32_to_cpu(raw_super->secs_per_zone);
876 	sbi->total_sections = le32_to_cpu(raw_super->section_count);
877 	sbi->total_node_count =
878 		(le32_to_cpu(raw_super->segment_count_nat) / 2)
879 			* sbi->blocks_per_seg * NAT_ENTRY_PER_BLOCK;
880 	sbi->root_ino_num = le32_to_cpu(raw_super->root_ino);
881 	sbi->node_ino_num = le32_to_cpu(raw_super->node_ino);
882 	sbi->meta_ino_num = le32_to_cpu(raw_super->meta_ino);
883 	sbi->cur_victim_sec = NULL_SECNO;
884 	sbi->max_victim_search = DEF_MAX_VICTIM_SEARCH;
885 
886 	for (i = 0; i < NR_COUNT_TYPE; i++)
887 		atomic_set(&sbi->nr_pages[i], 0);
888 
889 	sbi->dir_level = DEF_DIR_LEVEL;
890 	sbi->need_fsck = false;
891 }
892 
893 /*
894  * Read f2fs raw super block.
895  * Because we have two copies of super block, so read the first one at first,
896  * if the first one is invalid, move to read the second one.
897  */
898 static int read_raw_super_block(struct super_block *sb,
899 			struct f2fs_super_block **raw_super,
900 			struct buffer_head **raw_super_buf)
901 {
902 	int block = 0;
903 
904 retry:
905 	*raw_super_buf = sb_bread(sb, block);
906 	if (!*raw_super_buf) {
907 		f2fs_msg(sb, KERN_ERR, "Unable to read %dth superblock",
908 				block + 1);
909 		if (block == 0) {
910 			block++;
911 			goto retry;
912 		} else {
913 			return -EIO;
914 		}
915 	}
916 
917 	*raw_super = (struct f2fs_super_block *)
918 		((char *)(*raw_super_buf)->b_data + F2FS_SUPER_OFFSET);
919 
920 	/* sanity checking of raw super */
921 	if (sanity_check_raw_super(sb, *raw_super)) {
922 		brelse(*raw_super_buf);
923 		f2fs_msg(sb, KERN_ERR,
924 			"Can't find valid F2FS filesystem in %dth superblock",
925 								block + 1);
926 		if (block == 0) {
927 			block++;
928 			goto retry;
929 		} else {
930 			return -EINVAL;
931 		}
932 	}
933 
934 	return 0;
935 }
936 
937 static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
938 {
939 	struct f2fs_sb_info *sbi;
940 	struct f2fs_super_block *raw_super = NULL;
941 	struct buffer_head *raw_super_buf;
942 	struct inode *root;
943 	long err = -EINVAL;
944 	bool retry = true;
945 	int i;
946 
947 try_onemore:
948 	/* allocate memory for f2fs-specific super block info */
949 	sbi = kzalloc(sizeof(struct f2fs_sb_info), GFP_KERNEL);
950 	if (!sbi)
951 		return -ENOMEM;
952 
953 	/* set a block size */
954 	if (unlikely(!sb_set_blocksize(sb, F2FS_BLKSIZE))) {
955 		f2fs_msg(sb, KERN_ERR, "unable to set blocksize");
956 		goto free_sbi;
957 	}
958 
959 	err = read_raw_super_block(sb, &raw_super, &raw_super_buf);
960 	if (err)
961 		goto free_sbi;
962 
963 	sb->s_fs_info = sbi;
964 	/* init some FS parameters */
965 	sbi->active_logs = NR_CURSEG_TYPE;
966 
967 	set_opt(sbi, BG_GC);
968 
969 #ifdef CONFIG_F2FS_FS_XATTR
970 	set_opt(sbi, XATTR_USER);
971 #endif
972 #ifdef CONFIG_F2FS_FS_POSIX_ACL
973 	set_opt(sbi, POSIX_ACL);
974 #endif
975 	/* parse mount options */
976 	err = parse_options(sb, (char *)data);
977 	if (err)
978 		goto free_sb_buf;
979 
980 	sb->s_maxbytes = max_file_size(le32_to_cpu(raw_super->log_blocksize));
981 	sb->s_max_links = F2FS_LINK_MAX;
982 	get_random_bytes(&sbi->s_next_generation, sizeof(u32));
983 
984 	sb->s_op = &f2fs_sops;
985 	sb->s_xattr = f2fs_xattr_handlers;
986 	sb->s_export_op = &f2fs_export_ops;
987 	sb->s_magic = F2FS_SUPER_MAGIC;
988 	sb->s_time_gran = 1;
989 	sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
990 		(test_opt(sbi, POSIX_ACL) ? MS_POSIXACL : 0);
991 	memcpy(sb->s_uuid, raw_super->uuid, sizeof(raw_super->uuid));
992 
993 	/* init f2fs-specific super block info */
994 	sbi->sb = sb;
995 	sbi->raw_super = raw_super;
996 	sbi->raw_super_buf = raw_super_buf;
997 	mutex_init(&sbi->gc_mutex);
998 	mutex_init(&sbi->writepages);
999 	mutex_init(&sbi->cp_mutex);
1000 	init_rwsem(&sbi->node_write);
1001 	sbi->por_doing = false;
1002 	spin_lock_init(&sbi->stat_lock);
1003 
1004 	init_rwsem(&sbi->read_io.io_rwsem);
1005 	sbi->read_io.sbi = sbi;
1006 	sbi->read_io.bio = NULL;
1007 	for (i = 0; i < NR_PAGE_TYPE; i++) {
1008 		init_rwsem(&sbi->write_io[i].io_rwsem);
1009 		sbi->write_io[i].sbi = sbi;
1010 		sbi->write_io[i].bio = NULL;
1011 	}
1012 
1013 	init_rwsem(&sbi->cp_rwsem);
1014 	init_waitqueue_head(&sbi->cp_wait);
1015 	init_sb_info(sbi);
1016 
1017 	/* get an inode for meta space */
1018 	sbi->meta_inode = f2fs_iget(sb, F2FS_META_INO(sbi));
1019 	if (IS_ERR(sbi->meta_inode)) {
1020 		f2fs_msg(sb, KERN_ERR, "Failed to read F2FS meta data inode");
1021 		err = PTR_ERR(sbi->meta_inode);
1022 		goto free_sb_buf;
1023 	}
1024 
1025 	err = get_valid_checkpoint(sbi);
1026 	if (err) {
1027 		f2fs_msg(sb, KERN_ERR, "Failed to get valid F2FS checkpoint");
1028 		goto free_meta_inode;
1029 	}
1030 
1031 	/* sanity checking of checkpoint */
1032 	err = -EINVAL;
1033 	if (sanity_check_ckpt(sbi)) {
1034 		f2fs_msg(sb, KERN_ERR, "Invalid F2FS checkpoint");
1035 		goto free_cp;
1036 	}
1037 
1038 	sbi->total_valid_node_count =
1039 				le32_to_cpu(sbi->ckpt->valid_node_count);
1040 	sbi->total_valid_inode_count =
1041 				le32_to_cpu(sbi->ckpt->valid_inode_count);
1042 	sbi->user_block_count = le64_to_cpu(sbi->ckpt->user_block_count);
1043 	sbi->total_valid_block_count =
1044 				le64_to_cpu(sbi->ckpt->valid_block_count);
1045 	sbi->last_valid_block_count = sbi->total_valid_block_count;
1046 	sbi->alloc_valid_block_count = 0;
1047 	INIT_LIST_HEAD(&sbi->dir_inode_list);
1048 	spin_lock_init(&sbi->dir_inode_lock);
1049 
1050 	init_ino_entry_info(sbi);
1051 
1052 	/* setup f2fs internal modules */
1053 	err = build_segment_manager(sbi);
1054 	if (err) {
1055 		f2fs_msg(sb, KERN_ERR,
1056 			"Failed to initialize F2FS segment manager");
1057 		goto free_sm;
1058 	}
1059 	err = build_node_manager(sbi);
1060 	if (err) {
1061 		f2fs_msg(sb, KERN_ERR,
1062 			"Failed to initialize F2FS node manager");
1063 		goto free_nm;
1064 	}
1065 
1066 	build_gc_manager(sbi);
1067 
1068 	/* get an inode for node space */
1069 	sbi->node_inode = f2fs_iget(sb, F2FS_NODE_INO(sbi));
1070 	if (IS_ERR(sbi->node_inode)) {
1071 		f2fs_msg(sb, KERN_ERR, "Failed to read node inode");
1072 		err = PTR_ERR(sbi->node_inode);
1073 		goto free_nm;
1074 	}
1075 
1076 	/* if there are nt orphan nodes free them */
1077 	recover_orphan_inodes(sbi);
1078 
1079 	/* read root inode and dentry */
1080 	root = f2fs_iget(sb, F2FS_ROOT_INO(sbi));
1081 	if (IS_ERR(root)) {
1082 		f2fs_msg(sb, KERN_ERR, "Failed to read root inode");
1083 		err = PTR_ERR(root);
1084 		goto free_node_inode;
1085 	}
1086 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1087 		iput(root);
1088 		err = -EINVAL;
1089 		goto free_node_inode;
1090 	}
1091 
1092 	sb->s_root = d_make_root(root); /* allocate root dentry */
1093 	if (!sb->s_root) {
1094 		err = -ENOMEM;
1095 		goto free_root_inode;
1096 	}
1097 
1098 	err = f2fs_build_stats(sbi);
1099 	if (err)
1100 		goto free_root_inode;
1101 
1102 	if (f2fs_proc_root)
1103 		sbi->s_proc = proc_mkdir(sb->s_id, f2fs_proc_root);
1104 
1105 	if (sbi->s_proc)
1106 		proc_create_data("segment_info", S_IRUGO, sbi->s_proc,
1107 				 &f2fs_seq_segment_info_fops, sb);
1108 
1109 	if (test_opt(sbi, DISCARD)) {
1110 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
1111 		if (!blk_queue_discard(q))
1112 			f2fs_msg(sb, KERN_WARNING,
1113 					"mounting with \"discard\" option, but "
1114 					"the device does not support discard");
1115 	}
1116 
1117 	sbi->s_kobj.kset = f2fs_kset;
1118 	init_completion(&sbi->s_kobj_unregister);
1119 	err = kobject_init_and_add(&sbi->s_kobj, &f2fs_ktype, NULL,
1120 							"%s", sb->s_id);
1121 	if (err)
1122 		goto free_proc;
1123 
1124 	if (!retry)
1125 		sbi->need_fsck = true;
1126 
1127 	/* recover fsynced data */
1128 	if (!test_opt(sbi, DISABLE_ROLL_FORWARD)) {
1129 		err = recover_fsync_data(sbi);
1130 		if (err) {
1131 			f2fs_msg(sb, KERN_ERR,
1132 				"Cannot recover all fsync data errno=%ld", err);
1133 			goto free_kobj;
1134 		}
1135 	}
1136 
1137 	/*
1138 	 * If filesystem is not mounted as read-only then
1139 	 * do start the gc_thread.
1140 	 */
1141 	if (test_opt(sbi, BG_GC) && !f2fs_readonly(sb)) {
1142 		/* After POR, we can run background GC thread.*/
1143 		err = start_gc_thread(sbi);
1144 		if (err)
1145 			goto free_kobj;
1146 	}
1147 	return 0;
1148 
1149 free_kobj:
1150 	kobject_del(&sbi->s_kobj);
1151 free_proc:
1152 	if (sbi->s_proc) {
1153 		remove_proc_entry("segment_info", sbi->s_proc);
1154 		remove_proc_entry(sb->s_id, f2fs_proc_root);
1155 	}
1156 	f2fs_destroy_stats(sbi);
1157 free_root_inode:
1158 	dput(sb->s_root);
1159 	sb->s_root = NULL;
1160 free_node_inode:
1161 	iput(sbi->node_inode);
1162 free_nm:
1163 	destroy_node_manager(sbi);
1164 free_sm:
1165 	destroy_segment_manager(sbi);
1166 free_cp:
1167 	kfree(sbi->ckpt);
1168 free_meta_inode:
1169 	make_bad_inode(sbi->meta_inode);
1170 	iput(sbi->meta_inode);
1171 free_sb_buf:
1172 	brelse(raw_super_buf);
1173 free_sbi:
1174 	kfree(sbi);
1175 
1176 	/* give only one another chance */
1177 	if (retry) {
1178 		retry = 0;
1179 		shrink_dcache_sb(sb);
1180 		goto try_onemore;
1181 	}
1182 	return err;
1183 }
1184 
1185 static struct dentry *f2fs_mount(struct file_system_type *fs_type, int flags,
1186 			const char *dev_name, void *data)
1187 {
1188 	return mount_bdev(fs_type, flags, dev_name, data, f2fs_fill_super);
1189 }
1190 
1191 static struct file_system_type f2fs_fs_type = {
1192 	.owner		= THIS_MODULE,
1193 	.name		= "f2fs",
1194 	.mount		= f2fs_mount,
1195 	.kill_sb	= kill_block_super,
1196 	.fs_flags	= FS_REQUIRES_DEV,
1197 };
1198 MODULE_ALIAS_FS("f2fs");
1199 
1200 static int __init init_inodecache(void)
1201 {
1202 	f2fs_inode_cachep = f2fs_kmem_cache_create("f2fs_inode_cache",
1203 			sizeof(struct f2fs_inode_info));
1204 	if (!f2fs_inode_cachep)
1205 		return -ENOMEM;
1206 	return 0;
1207 }
1208 
1209 static void destroy_inodecache(void)
1210 {
1211 	/*
1212 	 * Make sure all delayed rcu free inodes are flushed before we
1213 	 * destroy cache.
1214 	 */
1215 	rcu_barrier();
1216 	kmem_cache_destroy(f2fs_inode_cachep);
1217 }
1218 
1219 static int __init init_f2fs_fs(void)
1220 {
1221 	int err;
1222 
1223 	err = init_inodecache();
1224 	if (err)
1225 		goto fail;
1226 	err = create_node_manager_caches();
1227 	if (err)
1228 		goto free_inodecache;
1229 	err = create_segment_manager_caches();
1230 	if (err)
1231 		goto free_node_manager_caches;
1232 	err = create_gc_caches();
1233 	if (err)
1234 		goto free_segment_manager_caches;
1235 	err = create_checkpoint_caches();
1236 	if (err)
1237 		goto free_gc_caches;
1238 	f2fs_kset = kset_create_and_add("f2fs", NULL, fs_kobj);
1239 	if (!f2fs_kset) {
1240 		err = -ENOMEM;
1241 		goto free_checkpoint_caches;
1242 	}
1243 	err = register_filesystem(&f2fs_fs_type);
1244 	if (err)
1245 		goto free_kset;
1246 	f2fs_create_root_stats();
1247 	f2fs_proc_root = proc_mkdir("fs/f2fs", NULL);
1248 	return 0;
1249 
1250 free_kset:
1251 	kset_unregister(f2fs_kset);
1252 free_checkpoint_caches:
1253 	destroy_checkpoint_caches();
1254 free_gc_caches:
1255 	destroy_gc_caches();
1256 free_segment_manager_caches:
1257 	destroy_segment_manager_caches();
1258 free_node_manager_caches:
1259 	destroy_node_manager_caches();
1260 free_inodecache:
1261 	destroy_inodecache();
1262 fail:
1263 	return err;
1264 }
1265 
1266 static void __exit exit_f2fs_fs(void)
1267 {
1268 	remove_proc_entry("fs/f2fs", NULL);
1269 	f2fs_destroy_root_stats();
1270 	unregister_filesystem(&f2fs_fs_type);
1271 	destroy_checkpoint_caches();
1272 	destroy_gc_caches();
1273 	destroy_segment_manager_caches();
1274 	destroy_node_manager_caches();
1275 	destroy_inodecache();
1276 	kset_unregister(f2fs_kset);
1277 }
1278 
1279 module_init(init_f2fs_fs)
1280 module_exit(exit_f2fs_fs)
1281 
1282 MODULE_AUTHOR("Samsung Electronics's Praesto Team");
1283 MODULE_DESCRIPTION("Flash Friendly File System");
1284 MODULE_LICENSE("GPL");
1285